The five landform regions that make up the United States are the West, Midwest, Northeast, Southwest and Southeast regions. The states that comprise these individual regions are grouped according to their locations on the continent, as well as the major physical features and climatic conditions that are common in these areas. Continue Reading.
In 1845, America tried buying huge parts of Mexican land that included present day California and New Mexico. When Mexico refused to part with its land, America tried using force. Mexico and America both maintained that the border was theirs. This led to the beginning of the Mexican America War that would last for two years (1846-48). America won the war decisively. Mexico had to give up California, New Mexico, Utah, Nevada and parts of Colorado, Wyoming and Arizona.
The war followed in the wake of the 1845 expansion of U.S. territory with the annexation of Texas. Texas had revolted against Mexico in the 1836 Texas Revolution, but Mexico continued to consider it part of its national territory. Annexation by the U.S. escalated the dispute between the nations into war.fter the declaration of war on May 13, 1846, U.S. forces invaded Mexican territory on two main fronts. The U.S. War Department sent a U.S. Cavalry force under Stephen W. Kearny to invade western Mexico from Jefferson Barracks and Fort Leavenworth, reinforced by a Pacific fleet under John D. Sloat.